BarryG,
Attention the codes P0500 and P0501 both deal with the speed sonsor but have a somewhat different meaning.
P0500 = NO Vehicle Speed sensor signal. Pretty self explaining.
P0501 = Vehicle Speed sensor performance.
That's a different beast. The PCM looks if the VSS output makes sense. Example. The truck is in OD. The transmission output shaft is turning at a certain speed. The VSS SHOULD give a certain output... . it does NOT match what it SHOULD be, voilà P0501 is set.
Looks like your VSS is intermitent, or has problems with the plugs or the wires.
That COULD cause some problem(s).
Marco
Attention the codes P0500 and P0501 both deal with the speed sonsor but have a somewhat different meaning.
P0500 = NO Vehicle Speed sensor signal. Pretty self explaining.
P0501 = Vehicle Speed sensor performance.
That's a different beast. The PCM looks if the VSS output makes sense. Example. The truck is in OD. The transmission output shaft is turning at a certain speed. The VSS SHOULD give a certain output... . it does NOT match what it SHOULD be, voilà P0501 is set.
Looks like your VSS is intermitent, or has problems with the plugs or the wires.
That COULD cause some problem(s).
Marco